NOTHING BUT THE TOOTH -- Silver fillings can last a lifetime

By Dr. Richard Greenberg

Thursday

Nov 29, 2018 at 3:01 AM

Q. I have been to my new dentist three times for cleaning only. I am 62 years old and have no problems that I am aware of. Every time I go, he wants to take out three silver fillings that were done when I was in college. He says they need to be replaced with new tooth-colored materials. So far, he hasn’t given me a reason why that I can accept. What should I do? -- Ms. A

A. To put it bluntly, change dentists. There is no reason at all to replace an existing restoration that is functioning well. I assume there is no decay around it or under it, as that would be a reason that would make sense to you. It sounds to me that he is replacing it for looks only and looks are in the eye of the beholder. If the silver color does not bother you or anyone whose opinion you value, then absolutely leave it alone. I personally have placed silver fillings in the late 1960s that are still in place with no recurrent decay and continuing to function very well.

Could there be a profit motive on the part of the dentist? Certainly there could be, but let us give him the benefit of the doubt. Maybe he thinks there is something wrong with a mercury containing dental material. If there was something wrong with the mercury, we would have had an insurmountable number of people adversely affected through the last 70-plus years. Over those years, there have been a few times where it has been reported from some sources that mercury in silver fillings would cause various health issues. Those claims have never been substantiated and even the American Dental Association has nothing negative to say about the use of silver amalgam.

Silver amalgam is far easier for the dentist to place, is far less expensive to the dentist and to the patient, so why would the dentist not use it more regularly? For so many years, it was the most-popular filling material. But I believe for one reason and one reason only, these materials fell out of favor. They lasted too long, were too inexpensive and if placed and polished 24 hours later, had the potential to last a lifetime. Dental practitioners were looking for work to do and the idea of adding in the “look good” component was appealing to uneducated and uninformed patients. The dentists quickly agreed to replace these functional silver restorations and the dentist’s workload increased exponentially, their pocketbooks started to fill so much faster, and guess what? These new white or tooth-colored materials failed on a regular basis.

In June, a monthly publication from the only independent dental research organization in the country put out an edition discussing the “Epidemic of Cervical Caries in Class II Resin Restorations.” These restorations are ones placed by dentists using resin or tooth-colored materials to restore decay between teeth. Why the epidemic? Simply because of operator error. That is right. They just were not done correctly. Reason simply is that to do them correctly takes a high level of expertise, as well as patience and a gifted surgical technique. Not that common among our profession and hence the explosion of failures.

On the other hand, placing silver amalgam is nowhere near as difficult to do for the dentist, is far more forgiving of slight errors and has the very distinct advantage of corroding at the edges where the filling meets the tooth. This corrosion is of no consequence to you and it actually blocks the ingress of bacteria at these margins. The long-term effect is that decay is rarely seen around an intact silver amalgam dental restoration. They just last much longer.

When the resin filling fails, what affect does that failure have on you? Well when the failure occurs, the restoration has to be redone. Another visit to the dentist. Another shot. Another drilling, and of course another fee. Besides taking money from you and giving it to the dentist, the drilling damages your tooth. The filling usually gets bigger, making it weaker and harder to do and also can potentially damage the tooth. Drilling over and over on a tooth increases the chances of nerve damage to that tooth and if that occurs, root canal therapy is indicated. More work, more drilling, more shots and more money transfer. From you to the dentist.

Ms. A, if your dentist was replacing the silver filling in your mouth because of decay that developed around it or because your tooth fractured, then there is a rationale. But using an inferior tooth-colored material is a poor selection for replacement. Remember that. Silver amalgam could be used again, if finances allow then gold could be selected as the material of choice. Gold has the potential to always last a lifetime. Silver amalgam has that potential in small- to medium-size restorations. Good for you. Good for your teeth. Bad for the dentist’s pocketbook.

Do not worry about their pocketbooks; they seem to be getting along fine without promoting work that is not needed.

-- Dr. Richard Greenberg of Ipswich practiced dentistry for 45 years after having attended dental school at Columbia University, where he was later an associate clinical professor of restorative dentistry and facilitator of the course of ethics. Do you have a dental question or comment about the column? Email him at dr.richard@nothingbutthetooth.org.